The present invention relates to sequin feeder device for use in sewing machines which sew a sequin onto a sewing workpiece while severing the sequin from a ribbon or strip of continuously-connected sequins.
One example of sequin feeder devices for use in sewing machines is known from Japanese Patent Application Laid-open Publication No. 2004-167097. This known sequin feeder device includes a feed lever for feeding a strip of a multiplicity of continuously-connected sequins (spangles) played out or let out from a reel and then placed on the upper surface of a support plate and a lock lever for immovably locking the strip of continuously-connected sequins (continuous sequin strip) at the end of the sequin feeding operation by the feed lever. In this type of sequin feeder device, the feed lever feeds the strip of continuously-connected sequins (continuous sequin strip) by causing its distal-end engaging portion to engage a sewing hole of a predetermined one of the sequins of the continuous sequin strip and moving forward the distal-end engaging portion together with the predetermined sequin. Through repetition of such forward (or advancing) movement and subsequent rearward (or retracting) movement of the feed lever, sequins of the continuous sequin strip can be sequentially engaged and fed, by the distal-end engaging portion, one sequin at a time. The lock lever, which is pivotably supported near the feed lever, is positioned in such a manner that an engaging claw provided at the distal end of the lock lever extends through a through-hole, formed in the feed lever, and normally biased, via a spring or the like, so that the engaging claw of the lock lever is brought into engagement with the sewing hole of one of the sequins. At the end of the sequin feeding operation by the feed lever, the engaging claw of the lock lever can immovably lock the continuous sequin strip by the engaging claw engaging the sequin hole in one of the sequins of the strip. Operational relationship between the feed lever and the lock lever is briefed below. As the feed lever retracts, the peripheral edge of the through-hole in the feed lever abuts against the lock lever to push rearward the lock lever, so that the engagement, by the engaging claw of the lock lever, of the sewing hole of the sequin can be released. Conversely, as the feed lever advances, the peripheral edge of the through-hole in the feed lever disengages from the lock lever so that the lock lever is brought into a freely pivotable state, and thus, the biasing force of the spring or the like causes the engaging claw of the lock lever to abut against the upper surface of a predetermined one of the sequins. Then, as the feed lever further advances, the engaging claw having abutted against the sequin slides on the sequin's upper surface relatively to the latter. When the feed lever has completed the sequin feeding operation, the engaging claw of the lock lever engages the sewing hole of a sequin to thereby immovably lock the continuous sequin strip.
In the conventionally-known sequin feeder device arranged in the aforementioned manner, the lock lever, abutting against the peripheral edge of the through-hole of the feed lever, pivots in a direction away from a sequin in response to the retracting movement of the feed lever and in a direction toward the sequin in response to the advancing operation of the feed lever. In other words, during the advancing or sequin feeding stroke of the feed lever, the peripheral edge of the through-hole of the feed lever functions to control timing at which the engaging claw of the lock lever starts moving down toward the sequin. Length of one stroke of the advancing and retracting movement (i.e., sequin feeding operation) of the feed lever corresponds to the size of each sequin of the continuous sequin strip. The through-hole of the feed lever, on the other hand, has a relatively large size (particularly, a large length in the sequin feeding direction) so as to appropriately deal with sequins of various sizes, but the size of the through-hole is determined without adjustment of the moving-down timing of the engaging claw according to the sequin size being taken into account. Thus, during the advancing or sequin feeding operation of the feed lever in the conventionally-known sequin feeder device, the lock lever is brought into the free state the moment it disengages the peripheral edge of the through-hole of the feed lever, so that the engaging claw would slide on the upper surface of the sequin over a relatively long distance, as noted above. Thus, depending on the material of the sequin, there would arise the inconvenience that the engaging claw forms an unwanted sliding mark in the surface of the sequin.
There are presently available sequins of various shapes. In recent years, modified sequins have appeared which have the sewing hole offset from the center of the sequin, as illustrated in FIGS. 14A and 14B, in order to enhance the decorativeness of a product with such sequins sewn thereto. However, the following inconveniences would be encountered in cases where sequins having the sewing hole offset from the sequin center as illustrated in FIGS. 14A and 14B are fed by the conventional sequin feeder device. Namely, because the through-hole of the feed lever of the conventional sequin feeder device has a relatively large size (particularly, a great length in the sequin feeding direction) as noted above, there is a possibility of the lock lever being brought into the free state at a position short of a boundary or connecting portion between the sequins, depending on the size of the sequins, as seen from FIGS. 15A and 15B. More specifically, FIG. 15A shows how the feed lever feeds a sequin having the sewing hole in the center of the sequin, while FIG. 15B shows how the feed lever feeds a sequin having the sewing hole offset from the center of the sequin. In each of the illustrated examples of FIGS. 15A and 15B, the engaging claw 33a of the lock lever 33 is resiliently abutting against the upper surface of the sequin (by the biasing force of the spring or the like). As the feed lever advances, the continuous sequin strip is fed in a direction of arrow A, and the engaging claw 33a slides in a direction of arrow B on the upper surfaces of adjoining sequins relatively to the latter. In the case where the sequins are of the type having the sewing hole in the sequin center, the engaging claw 33a slides on the connecting portion between the adjoining sequins onto the upper surface of the succeeding sequin (see FIG. 15A). On the other hand, in the case where the sequins are of the type having the dewing hole offset from the sequin center, the engaging claw 33a of the lock lever 33 slides over a region indicated by reference character “C” (where adjoining sequins are spaced apart from each other by a gap) remotely from the connecting portion because the engaging claw 33a has been adjusted in advance to fit into the offset sewing hole of each of the sequins. Thus, when the engaging claw 33a is located over the C region, it tends to get into the gap between the adjoining sequins due to the biasing force imparted to the lock lever 33. Then, as the feed lever further advances in this state, the engaging claw 33a, having gotten into the gap, interferes with the outer peripheral edge of the succeeding sequin, so that the continuous sequin strip would undesirably meander or deform away from the engaging claw 33a. 
Further, in the conventionally-known sequin feeder device, the sequin feeding operation is performed with only one point, where the distal end of the feed lever engages the sequin sewing hole, functioning as the supporting point. Thus, in the case where the sequins of the continuous sequin strip are of the type having the sewing hole offset from the center, particularly in a direction perpendicular to the feeding direction of the continuous sequin strip (as illustrated in FIGS. 14A, 14B, etc.), there would be produced a force that causes the continuous sequin strip to turn about the neighborhood of the connecting portion between adjoining sequins, which would undesirably deform the connecting portion and incline the sequins (about the vertical axis). Improved sequin feeder device constructed to avoid such an inconvenience has also been popularly known, which is equipped with a guide member for guiding a continuous sequin strip so as to allow the sequin strip to be fed straight in a predetermined feeding direction. Among examples of the conventionally-known guide members are one which has a pair of opposed left and right side walls for controlling positions of the left and right edges of the continuous sequin strip and in which the left and right side walls are integrally fixed with respect to each other, and one in which the opposed left and right side walls are dividable and adjustable in position relative to each other. The guide member of the first-mentioned type having the left and right side walls integrally fixed with respect to each other is replaceable with another one in accordance with the size of the sequin. In the guide member of the second-mentioned type having the dividable and adjustable the left and right side walls, on the other hand, the distance between the opposed left and right side walls is adjusted in accordance with the size of the sequin. However, these conventional guide members would present the following inconveniences. Namely, with the guide member of the second-mentioned type having the dividable and adjustable the left and right side walls, it is very cumbersome to adjust the distance between the left and right side walls in accordance with the size of the sequins; particularly, in the case where the sequin is of the type having the sewing hole offset from the center of the sequin, the adjusting operation tends to be very cumbersome because it is necessary to not only appropriately adjust the distance between the left and right side walls but also adjust the sewing hole to be located in vertical registry with the needle drop position. Further, where the sewing machine to which the guide member is applied is a multi-head sewing machine, such adjusting operation has to be performed for each and every one of the machine heads, and thus, the adjusting operation tends to be very time-consuming and lead to a very poor working efficiency. Furthermore, with the guide member of type having the left and right side walls integrally fixed with respect to each other, a plurality of the guide members corresponding to various sequin sizes have to be prepared, and thus, the necessary cost increases accordingly. Replacing the guide member of the first type with another one of the same type may be performed in a shorter time than adjusting the guide member of the second type. However, with the conventionally-known first-type guide member, it is at least necessary to appropriately adjust the fixed positions of the side walls and the replacing operation can not be performed so easily, so that relatively great amounts of time and labor would be required in actually using the guide member.